White screen and problems with psu

[BardiaMGTGC]

i upgraded my pc from phenom ii x4 955 from 2010 to an i5 7400 and rx 580 h110 m-c/ps 8gb of ram and some drives i didnt had enough money to get a psu so i used my old psu a 485 watt green psu

with my old gpu which needed no connectors gtx 1050 i had no problem but with my new second hand rx 580 (which is mining and everything is fine with it) i get white screen and crashes on gaming 

i tested watchdogs 2 forza horizon 4 and minecraft while streaming and encoding with gpu it crashed my whole pc and i forced shut down by case power button 
i had problems with it like pc turning on and off right after 
im changing to a 650 watt psu today and i just wanted to know if my psu is the problem

[driftz240]

Since you said your changing to a 650 watt psu today then i assume youve already have it so just test it out and see. Also you didnt mention what models either of the power supplies were so its hard to tell.